The field of the disclosure relates generally to communication networks and more specifically to fail-safe Ethernet communication networks.
High-speed communication channels are often designed as or considered to be non-vital parts of a vital system due to the level of difficulty that must be overcome to make the communication channels fail-safe and highly available. Fail-safety and availability issues in high-speed communication systems have been addressed. For example, an Attached Resource Computer NETwork (ARCnet) and a Token Ring network allow all nodes to have equal access to a network. Equal access to the network provides a predictable maximum transmission time dependent on the size of the data being transmitted. However, such technologies are typically proprietary. This limited the standardization and acceptance of these technologies, and therefore, the availability of supporting hardware/software. This limited the standardization and acceptance of supporting hardware/software in the market, which in turn hindered the application and growth of these technologies.
In contrast, Ethernet is an open network and has been standardized by the IEEE and the ISO. Various types of Ethernet hardware (e.g., PHY, MAC, switch, etc.), physical media, software, and protocols are consistently being developed by different vendors. Ethernet even adopted some features of competing technologies, for example, the star topology of ARCnet. The speed of matured Ethernet products was also quickly increasing, almost exponentially, from ten megabit per second (10 Mbps), to one hundred Mbps, and to as high as one gigabit per second (1 Gbps) and ten Gbps. Ethernet is not only widely accepted, but it also has survived the rapid changes of communication networking markets over time.
It would be advantageous to interface a high-speed communication network, such as Ethernet, with a fail-safe system, while maintaining a high level of safety and availability. The safety of a system can be measured against criteria such as the Security Integrity Levels (SIL) defined by the European Committee for Electrotechnical Standardization (CENELEC). Additionally, use of a standardized solution, such as Ethernet hardware/software, facilitates using economical hardware and software, which are readily available from the market.